A/C pressure readings on my 2000 Escalade

[SunlitComet]

I hope you have the correct orifice tube in there.

Oh the possibilities.

 

[Stresst]

Assuming all fans are working, it appears almost normal for your humidity levels.

I am leaning on a tad overcharged, and that will be worst at idle with low airflow.

If undercharged it will be colder than normal at idle and cycle like a mofo when on the freeway.

---------- Post added at 05:07 PM ---------- Previous post was at 05:07 PM ----------

I hope you have the correct orifice tube in there.

Actually I dont. I have one out of a ford with 2 o-rings. I just came across a ac delco orifice made for 105 degree weather. Gonna give that a try. Once I get the new orifice gonna bring it to a shop that has a machine that can put the freon back by weight. But capacity now becomes an issue. Some say 2.75 while others say 3.5lbs.

---------- Post added at 08:43 PM ---------- Previous post was at 08:36 PM ----------

I see Autozone sells one by Santech:


Part Number: MT0628 AVAILABILITY:STORE PICK UP SPECIAL ORDERVisit your local store to special order.SHIP TO HOMESPECIAL ORDERShips within 3-5 business days.Features & Benefits

The variable orifice valve (VOV) was developed to improve the performance of a standard fixed orifice tube (FOT). A variable orifice valve will significantly improve A/C system performance at idle and low speed driving, especially in high temperature climates. The variable orifice valve is a direct replacement for the original fixed orifice tube. No physical modification is required to upgrade the A/C system.
•Improves system performance in hot idle situations
•Delivers five to twelve degree colder vent temperatures
•Improves city driving fuel economy and emissions
•Reduces compressor load to help extend compressor life

I wonder????

 

[gpracer1]

I had a VOT in my 93 that I converted to 134a and it was great, but it didnt have rear air.

I have not found a VOT yet for a tahoe with rear air.

One thing I forgot to mention when you charge a system.
When you are low, the low psi line going into the evap will be colder than the line coming out. When they are both about the same coldness, you have enough freon to flood the entire evap, but try not to add any more when you reach that point.

 

[SunlitComet]

Actually I dont. I have one out of a ford with 2 o-rings. I just came across a ac delco orifice made for 105 degree weather. Gonna give that a try. Once I get the new orifice gonna bring it to a shop that has a machine that can put the freon back by weight. But capacity now becomes an issue. Some say 2.75 while others say 3.5lbs.

---------- Post added at 08:43 PM ---------- Previous post was at 08:36 PM ----------

I see Autozone sells one by Santech:


Part Number: MT0628 AVAILABILITY:STORE PICK UP SPECIAL ORDERVisit your local store to special order.SHIP TO HOMESPECIAL ORDERShips within 3-5 business days.Features & Benefits

The variable orifice valve (VOV) was developed to improve the performance of a standard fixed orifice tube (FOT). A variable orifice valve will significantly improve A/C system performance at idle and low speed driving, especially in high temperature climates. The variable orifice valve is a direct replacement for the original fixed orifice tube. No physical modification is required to upgrade the A/C system.
•Improves system performance in hot idle situations
•Delivers five to twelve degree colder vent temperatures
•Improves city driving fuel economy and emissions
•Reduces compressor load to help extend compressor life

I wonder????

You know I think that might do it.

 

[Stresst]

I just found the santech on ebay for 14 bucks. We will see if it works!

 

[gpracer1]

I put 2.75 pounds like the sticker said and it blows great. I would put in another .25-.50 so it wont cycle as much at higher rpms on the highway since it could handle the higher pressures with the airflow, but at idle it would suffer till I get the efans.

 

[Stresst]

I put 2.75 pounds like the sticker said and it blows great. I would put in another .25-.50 so it wont cycle as much at higher rpms on the highway since it could handle the higher pressures with the airflow, but at idle it would suffer till I get the efans.

Im still on the fence which is the "rite way". I spoke to the guy who sold me the lines and they are the same as the suburban. So technically the tahoes/escalades with rear air are "suburbans" when it comes to capacity.

Let me ask a stupid question, how do you know when it cycles if your on the highway?

 

[SunlitComet]

Four Door Utility with C69 2.75
Suburban with C69 3.5

C69 = Rear Air Conditioning

This is factory data.

 

[Stresst]

Four Door Utility with C69 2.75
Suburban with C69 3.5

C69 = Rear Air Conditioning

This is factory data.

I hear ya! But there is no differance between the C69 tahoe and a suburban from what im being told. I was told I can remove my a/c and have it installed directly into a suburban. IDK.

 

[gpracer1]

Im still on the fence which is the "rite way". I spoke to the guy who sold me the lines and they are the same as the suburban. So technically the tahoes/escalades with rear air are "suburbans" when it comes to capacity.

Let me ask a stupid question, how do you know when it cycles if your on the highway?

When I drive on the highway at say 55 mph and 1700 or so rpms, it blows around 35 degrees with the digital thermometer, if I go faster (higher rpms) the low side gets sucked down a few more psi/degrees and it trips the cycle switch at 23 psi. I can tell because the temp on the thermo will go up right away (been doing this for 20 years I can tell vent temp by hand +/- 2 degrees or so).
I am still looking for a 19-20 psi switch since I am in a dry climate and dont have to worry as much about freezing the evap.